Process of holding and performing an operation on the outer coil of a timepiece hair spring

ABSTRACT

A process for facilitating operations to be made on the outer coil of a timepiece hair spring consists in positioning the hair spring on a support and holding it by its inner end, and pressing together against the center the coils located on the side opposite the center of the location on the outer coil where it is desired to effect this operation in order to increase the spacing between the coils on the other side. A device for carrying out this process has a frame in which is mounted a rotating broach for maintaining the inner end of the hair spring and a horizontal slider moving in the direction of the broach and having a vertical finger intended to compress the coils of the hair spring.

tates Patent United 1,144,548 6/1915 Jones............................1,251,765

[72] Inventor UlrichLeupin 1/1918 Fonnesbeck. 10/1950Maheu........................

Bienne, Switzerland Stull Primary ExaminerAndrew R. Johasz m H 1 55 99NH 79 55 557 748 246 222 1 $7 99 1 2 99 07 w m3 SFA Q d N m In n 9mm flaAFP [73] Assignee Societe des Fabriques de Spriaux lReunis Bienne,Switzerland Feb. 28, 1968 Switzerland 2912/68 Assistant Examiner- DonaldD. Evenson [32] Priority Attorneys-Robert E. Burns and Emmanuel J.Lobato [54] PROCESS OF HOLDING AND PERFORMING AN OPERATION ON THE OUTERCOIL OF A ABSTRACT: A process for facilitating operations to be made onthe outer coil ofa timepiece hair spring consists in positioning thehair spring on a support and holding it b y its inner end, and pressingtogether against the center the coils located on the side opposite thecenter of the location on the outer coil where it is desired to effectthis operation in order to increase m M no tm 9 B 9. 6 n m m9flm l- "0WMW G W m. m m mm m w m mm AW m Hm m n m mm 1 EM C U MC 5 m T3 U I N. UH U Field oiSearch........ 269/38,40, 49; /89; 83/176; 81/6, 7.5

the spacing between the coils on the other side. A device for carryingout this process has a frame in which is mounted a rotating broach formaintaining the inner end of the hair spring and a horizontal slidermoving in the direction of the broach and having a vertical fingerintended to compress the coils of the hair spring 8 T N W MA m mm mm msD E H N U Q U 938,818 11/1969 Bowers........................

PROCESS OF HOLDING AND PERFORMING AN OPERATION ON THE OUTER COIL OF ATIMEIPIIECIE HAIR SPRING A timepiece hair spring generally must be madeto size by cutting a part of the outside coil. Aside from conventionalmeans such as shears or other cutting instruments, machines have alreadybeen suggested in which the hair spring is maintained on an anvil, adevice allowing to pinch the hair spring by a horizontal movement beforecutting it. The outer coil of the hair spring being located very nearthe neighboring coil,

' the cutting tool can be very fine and guided with great preci sion ifit is desired to avoid touching the coil next to the coil to be cut.

The present invention is directed to a process allowing to increasetemporarily the distance separating the outer coil from the neighboringcoil in such a way as to facilitate not only the cutting but alloperations to be carried out on the outer coil, such as securing to thecanon, forming or bending.

It has for its object a process for facilitating all operation to beeffected on the outer coil of a timepiece hair spring, characterized inthat the hair spring being positioned on a support and retained by itsinner end there are pressed together against the center the coilslocated on the side opposite relative to the center of the place on theouter coil where it is desired to effect the said operation, in such away as to increase the spacing between the coils on the other side.

The invention also has for its object a device for carrying out theprocess, characterized by the fact that it comprises a frame in which ismounted a rotating broach for maintaining the inner end of the hairspring and a horizontal slider moving in the direction of the broach andcarrying a vertical finger intended to compress the coils of the hairspring.

The accompanying drawing represents by way of example one embodiment ofadevice for cutting the outer end ofa hair spring.

FIG. 1 shows an elevational view of the device.

FIG. 2 shows a plan view thereof.

FIG. 3 shows the deformed hair spring.

The cutting process is illustrated by FIG. 3 which shows a hair spring 1secured by its inner end to a broach 2, the coils of the hair springbeing pressed together by a finger 3 against broach 2, and against thecollet if the hair spring is already provided with a collet, at a pointat least approximately opposed to the point on the outer coil that it isdesired to cut. The space between the outer coil and the neighboringcoil increases in such a way that it is easier to cut it without risk oftouching the neighboring coil.

The device used for this purpose comprises a frame 4 carrying an anvil 5of hard metal having a slot 6 for the passage of finger 3 and slot 7 forthe passage of knife 8 as well as marks 9 for setting the hair spring.The center of the anvil is occupied by a broach 2 rotatably mounted androtated by a knurled pulley lll overlapping the frame and connected to apulley 10 on the broach by a transmission belt 12. The broach terminatesin its upper part in a conical part intended to carry collet 13. It ishowever possible to use a hollow conical broach having a slot in whichcan engage directly the inner end of the hair spring which has not beenprovided with a collet.

Finger 3 is mounted on a horizontal slider 14 operable by a knurledbutton 15. As for knife 8, it is mounted on a vertical slider 16 movedby a knurled button 117, the slides 18 and 19 of the slider 16 beingthemselves mounted through a piece 20 on a horizontal slider 21 whosepath is limited by a stop 22. The knife has an oblique edge in which ismade a vertical nick whose bottom constitutes the blade of the knife,the hair spring being maintained laterally during cutting by the sidesof the nick.

Instead of moving the finger against the broach, it is naturallypossible to move the broach against a fixed stop.

What] claim is: 1. Process for performing an operation on the outer COllof timepiece hair spring, comprising positioning said hair spring on aflat support, holding said hair spring by its inner end, pressingtogether against the center the coils of said hair spring located on theside opposite relative to the center of the place on the outer coilwhere it is desired to effect said o eration, whereby to increase thespacing between the coils on the other side while maintaining the coilsof said hair spring in the general plane of said spring, and performingsaid operation on the outer coil of said hair spring while the spacingbetween the coils thereofon said other side is thus increased.

2. A process according to claim 1, wherein said operation is a cuttingoperation to cut said spring to proper size.

3. A process according to claim 2., wherein said cutting operation iseffected by a knife moved toward said support.

1. Process for performing an operation on the outer coil of timepiecehair spring, comprising positioning said hair spring on a flat support,holding said hair spring by its inner end, pressing together against thecenter the coils of said hair spring located on the side oppositerelative to the center of the place on the outer coil where it isdesired to effect said operation, whereby to increase the spacingbetween the coils on the other side while maintaining the coils of saidhair spring in the general plane of said spring, and performing saidoperation on the outer coil of said hair spring while the spacingbetween the coils thereof on said other side is thus increased.
 2. Aprocess according to claim 1, wherein said operation is a cuttingoperation to cut said spring to proper size.
 3. A process according toclaim 2, wherein said cutting operation is effected by a knife movedtoward said support.